Fuse-supporting connection.



E. L. GRAUEL. FUSE SUPPORTING CONNECTIOIE, APPLIGATION FILED was, 1910.

Patented 0st, 11, 1910.

' specification.

TED STATES ea EDWIN L. GBAUEL, OF TROY, NEW YORK, ASSIGNOR T0 TRGYTELEPI-IONE SPECIALTY COMPANY, OF TROY, NEW YORK, A COBPOEATIGN 01? NEW"YORK.

FUSE-SUPPORTING CDBlNECTIOI'Il.

Specification of Letters Patent.

Patented @ct. 111.1914).

Application filed February 8, 19 10. Serial No. 542,733.

To all whom ii may concern:

Be it known that I, EDWIN L. GRAUEL, a citizen of the United States,residing at Troy, county of Rensselaer, and State of New York, haveinvented certain new and useful Improvements in Fuse-SupportingConnections, of which the following is a specification.

The invention relates to such improvements and consists ofthe novelconstruction and combination of parts hereinafter described andsubsequently claimed.

Reference may be had to the accompanying drawings, and the referencecharacters marked thereon, which form a part of this Similar charactersrefer to similar arts in the several figures therein.

The 0 ject of the invention is to provide a simple, cheaply constructedand easily operated supporting mechanism for an electricfuse which willinsure a stable contact between the fuse and the conductors which it isintended to connect by the interposition of a. safety fuse.

The invention consists of an electric-fuse with metallic terminals inthe form of screwthreaded lugs, one terminal being screwthreaded to theright and the other terminal to the left and a pair of yieldingplate-like conductors, a portion of each conductor be ing thinner thanthe space between the screw-threads on the lugs. such thin port-ionsbeing apertured. and the aperture-walls screw-threaded to receive andfit the threaded lugs, whereby the yieldiiig platelike conductors can besprung apart to insert the ends of the lugs in the plate-apertures, andby turning the fuse the threaded lugs will enter the plate-apertures anddraw the conductors into stable contact with metallic shoulders at theinner ends of the lugs. as

section.

I have ascertained that by employing plate-like conductors thinner atsome portions than the space between the screwthreads on thefuse-terminals, such conductors can be apertureo and screw-threaded atsuch thin portions to receive mafia either fuse-terminal, whetherscrew-threaded to the right or to the left. Such an arrangement greatlyfacilitates the operation of changing fuses, or inserting a new fuse forone blown out, as it makes no difference which fuse-terminal is insertedin either of the terminal-rcceiving apertures. 4

When the plate-like conductor containing the apertures is thinner thanthe space between two threads, it is obvious that a whole thread, thatis. a thread making a complete circuit of the aperture, cannot beinserted in the aperture-wall. therefore the threads of thescrew-threaded lug inserted in such aperture will catch and coact withthe aperturethread, whether the thread on the lug or terminal is cut tothe right or the left.

By having the lugs provided one with a right and the other with a.left-hand thread, it is only necessary to rotate them by rotating thefuse-body to which they are con-. nected to insert such lugs in thethreaded aperture and draw the plates and lug-shoulders .into solid andpermanent contact without the use of detachable screw-threaded nutsadapted to be screwed onto the ends of the lugs which project throughthe plate-like conductors.

Referring to the drawings,-l igure 1 is a top-plan view of aninsulator-block having a pair of electric-fuses suppoi'ted byelectricconductors by means of my improved supporting connections, oneof the fuse-bodies beingshown partly in central longitudinal Fig. 2 is aside elevation of the same. Fig. 3 is a plan view of the fuse-bodydetached from the conductors. Fig. 4c is a View similar to that shown inFig. 2, with the fuse-body detached. Fig. 5 is a horizontalcross-section of one of the plate-like conductors, taken on the brokenline 55 in Fig. 4, shown upon an enlarged scale. Fig. (l is a frontelevation of one of the plate like conductors detached. showing amodified form of screw-receiving aperture. Fig. 7 is a Tvertical sectionof the same, taken on the broken line 7-7 in Fig. 6. v

1 is an insulator-block which may be made of porcelain or otherinsulatingmatea by the dotted line 19. It is obvious from an ably madeof sheet-metal strips bent to form a right angle, are secured to theblock as by the screws 3, and connected in any known manner with theline-conductors (not shown). The terminals, 4, similar to the terminals2, are secured to the block as by screws, 5, and may be connected withinstallation-lines (not shown) in any known manner. The upper ends ofthe upright portions of the terminals 2 and 4 are apertured near theirupper ends, and screw-threaded, as shown in Fig: 5, to receive thescrew-' threaded lugs, 7 and 8, which constitute the fuse-terminals. Thefuses are composed of a tubular insulating body-part, 10, provided ateach end with a metallic cap, 12, shown octagonal in cross-sectionalform for the purpose of receiving a wrench to rotate the same. The capsare provided at their outer ends with trunnions or lugs, 7 and 8.

The fusible wire, 15, passes through the body 10, as seen in Fig. 1, andinto the lugs 7 and 8, which are made hollow to receive the ends of thefuse-wire, each end having an electric-connection with one of the lugs,which may be formed by a drop of solder inserted through the outer endsof the apertures in the lugs. The lug 8 is screwthreaded to the left,that is, in a direction which requires the lug to be turned toward theleft hand of the person facing the screwtlireaded aperture, and the lug7 is screwthreaded to the right, that is, in a direction which requiresthe lug to be turned toward the right hand of the person facing thescrew-threaded aperture. It is obvious, therefore, that when the body10, or the caps 12, are rotated in one direction, both the lugs will atthe same time enter the screw-threaded apertures in the uprights 2 and4, and when the fuse-body is turned in the opposite direction the lugswill be withdrawn from the u ri hts 2 and 4:.

P a: In Fig. 5, which is made on a large scale, is shown one of suchscrew-threaded apertures, 17, the screw-thread on the lower side of theaperture being represented by' the j' solid line 18, and thescrew-thread on the upper side of the aperture being representedinspection of this Fig. 5 that the thread 18 does not make a completecircuit of the aperture,- thereby permitting the lug, screwthreadedeither to the left, or the right, to be inserted therein by turning thesame in the proper direction. r

I have -ascertained that when/ the platelike conductors are made ofexceedingly thin plates, or when the screw-receiving apertures thereinare countersunk, it is net necessary to insert a tap in such apertur 's'to produce threads for receiving the sciew-th eaded terminals of thefuse. T have 'shbwn i Figs.

and 7 such modified form of construction,

wherein the aperture 22is countersunk on each of the opposite sides ofthe plate, thereby torrning the beveled surfaces 23 and the extremelythin edge 24 surrounding the aperture. It is unnecessary to insert ascrewthreading tap in such an aperture to adapt it to receive the rightand left threaded fuseterminals. The threads on such terminals willthemselves produce the necessary conformation of the aperture-walls tocause such walls to coact with the screw-threads on the fuse-terminals.Suchcoaction of the parts causes the yielding conductors to approacheach other, or recede, as the fuse-body is turned either in onedirection or the other, in the same manner that thicker aperturewallswould do if they had been previously 1 tapped and provided withscrew-threads to correspond with the threads on the fuseterminals. Theyielding conductor-plates 2, are preferably formed of resilient metal,and normally extend convergently upward, as shown in Fig. 3, with theirupper ends a distance apart somewhat less than the total length of thefuse, includingthe end-lugs 7 and 8. The upper ends of theconductorplates thus require to be forced apart to permit the fuse to beintroduced between them, and as soon as the lugs are brought oppositethe respective apertures in-the plates, 2, the resilient force of theplates w ll cause the screw-threads on the lugs to quickly bite or gripthe Walls of the aperture's'in the respective conductor-plates, and thefarther said lugs are screwed into said apertures the greater will bethe bite or grip of the screwthreads on the walls at thetop and bottomof the apertures, due to the fact that the plates are drawn toward eachother to a constantly increasing degree of obliqueness. By reason of thenormal convergence of the plates, the screw-threaded lugs are not onlycaused to grip the walls of the apertures more quickly, but willeffectively grip such walls even after the apertures have becomeconsiderably worn and enlarged by wear.

\Vhat I claim as new and desire to secure by Letters Patent is- 1. Thecombination with a pair of electricfuse terminals consisting of metalliclugs, screw-threaded, one to the right and the other to the left; of apair of yieldingly supported conductors apertured to receive. and'coac'twith the threaded lugs, respectively, and form stable contacts.

ing'thin'ner than the space between the screwthreads on the lugs, suchthin portions being apertured, and the aperture-walls threaded toreceive and fit the threaded lugs.

3.-The combination with a \fuse ving oppositely screw-threadedterminals; of a. In testimony whereof, I have hereunto pan ofconvergently arranged ylehihng reslhset my hand tlns 3th day ofFebruary, 1910.

ent conductor-plates apertnred toreceive and T PDWIB L. FT.

coact wlth sand terrmnals, respegtlvely, and J XL J J supported wlththan apertured portlons nor- 'ltnessesz a nlally separated by n spneeless than the l. S. FREEMAN,

length of said fuse. \V. J. GORMAN.

